The photo Microsoft used for the Windows XP default wallpaper is (mostly) untouched

Bliss, the photo taken by Charles O'Rear that later became the basis for the default wallpaper in Microsoft's Windows XP OS was not altered by O'Rear but did get a color boost for its wallpaper use

From Neowin:

Windows XP support ends one week from today but, as we learned, the 12-year old operating system will still be used by a ton of PCs worldwide after that day has come and gone. That also means many PCs will still have the Windows XP default wallpaper, depicting a location of green rolling hills, running in the background.

But where did that idyllic view come from? As CNet Australia reports, the original photo that Microsoft used as the basis for the wallpaper was taken back in 1996 by photographer Charles O'Rear using a Mamiya RZ67 film camera. The actual location is in the wine country of Northern California (you can check out the exact spot on Bing Maps).